Protective sleeve



1366- 1966 D. A. CUTLER PROTECTIVE SLEEVE Filed Aug. 21, 1964 United States Patent 3,292,535 PROTECTIVE SLEEVE David A. Cutler, Philadelphia, Pa., assignmto Triangle Publications, Inc., Philadelphia, Pa., a corporation of Delaware Filed Aug. 21, 1964, Ser. No. 391,124 7 Claims. (Cl. 101375) This invention relates to printing cylinders of the type used in rotogravure printing and has for an object the provision of a non-metallic sleeve assembly for protecting the ends of the printing cylinder from corrosion by chrome and copper plating electrolytes, engraving and etchants and for preventing printing ink buildup on the ends of the printing cylinders and on the shafts of the printing cylinders.

As will be understood by those skilled in the art, it is of utmost importance that the printing surface of the cylinder shall be smooth and shall be round or cylindrical within extremely narrow limits. To achieve at low cost the needed accuracies regarding smoothness,that is, a highly polished surface, and also the accuracy within which the diameter is maintained, resort has been had to the utilization of copper shells plated directly on a relatively heavy cylindrical body, generally of a ferrous metal. Ultimately, copper has been plated directly on the ferrous cylinder, thereafter brought to needed final dimensions, and subsequently used for rotogravure printing. In some instances, the impressions on the cylinder have been removed by grinding and the surface again polished preparatory to the development thereon of a new material to be utilized in the rotogravure printing. Additional copper has been plated onto the cylinder as needed. It has also been proposed to strip the copper shell from the cylinder and to produce a new shell by electroplating.

It is the purpose of the present invention to prevent inks used in rotogravure printing from adhering to the cylinder ends and shaft extensions and to provide protection against the corrosive character of the electrolyte used in the plating and etching operations.

In carrying out the invention in one form thereof, there is provided a sleeve of non-metallic acid-, electrolyteand ink-resisting material preferably in close-setting relationship with the shaft extensions and terminating in an outwardly extending flange portion having an outturned end which is held in a peripheral groove of the cylinder in manner to form an impervious seal. For further objects and advantages of the invention, reference is to be had to the accompanying drawing in which:

FIG. 1 is a side view partly in section of a printing cylinder for rotogravure process; and

' FIG. 2 is a partial end view of the cylinder of FIG. 1.

Referring to FIG. 1, there is shown a cylinder 10, preferably hollow and supported by shaft extension at the respective ends. One of these, shaft extension 11, is shown. The shaft is suitably supported in bearings, generally indicated at 12. The bearings 12 support the cylinder while it is in an electroplating bath, while it is in use in rotogravure printing, and while it is in a grinding machine in which an outer layer 13, such as copper, may be in part or in whole removed.

The inks utilized in rotogravure printing have relatively low surface tension and otherwise creep and dry on other than the printing surfaces. They are particularly bothersome in building up layer-s on the ends of the cylinders and along the supporting shafts, thus presenting contaminate problems in respect to the electrolyte and staining problems in the handling of printing cylinders. The ends of the cylinders and the shaft extensions also are subject to attack by the electrolyte which is quite corrosive.

In accordance with the present invention, a sleeve 14 made of a synthetic resin, such as polytetrafluoroethylene, generally available on the market under the trademark Teflon, extends over the exposed portion of each shaft extension. The cylindrical portion of the sleeve 14 is clamped to the shaft extension by a stainless steel slinger ring 15 provided with an overhanging lip 15a. Alternately, the ring 15 may be constructed of Teflon. The ring 15 when elevated in temperature expands and is slipped into place over the reduced portion 11a of the shaft extension until it abuts against a shoulder 11b of the shaft extension. The ring is cooled to bring the overhanging lip 15a tightly against the end of the sleeve 14 and also to produce a shrink-fit to the shaft extension 11. Thus, there is provided a leakproof seal between the Teflon sleeve 14 and the shaft extension.

The Teflon sleeve 14 may also be heated first and shrink-fitted to the exposed portion of each shaft extension so as to provide a more positive seal.

The sleeve 14 is fairly thick, i.e., about A", and terminates in the curved region between the end of the cylinder and its shaft extension. In order to protect the end of the cylinder, the sleeve further includes a flat flange portion 14b having a conical section 14a. The conical section 14a is adhesively secured to cylindrical portion of sleeve 14 in the curved region 110. The flange portion 14b also has a cylindrical extension 14c parallel to the axis of the cylinder and nesting within a peripheral groove 10a of cylinder 10. The cylindrical extension 14c is tightly clamped in place by a locking ring 16. The locking ring may have a slight taper to increase the leakproof seal it provides for the end face of cylinder 10 which is to be protected.

It is understood, of course, that the sleeve assembly as a whole may be made in one piece through the arrangement providing the thicker sleeve portion 14 to which there is adhesively attached a conical thinner portion 14a is satisfactory.

Though Teflon has been found highly satisfactory in providing the needed protection for the ends of the cylinder and the shaft extensions because of its chemical inertness in respect to the electrolyte or plating baths as well as its ability to resist wetting by an accumulation thereon of printing inks, it is to be understood that other synthetic resins or plastic materials may be utilized as long as they are chemically inert to both the electrolyte baths and printing inks. For example, synthetic resins such as polytetrafluoroethylene, available under trade name of Teflon; polychlorotrifluoroethylene, KEL-F; FEP .fluorocarbons; and vinyl chloride and vinyl chlorideacetate can be used within the scope of the present invention.

The electrolyte baths themselves are well known to those skilled in the art of plating and can be any of the kind used for adding to or removing from the surface of the cylinder 10 copper or other metals which are sometimes used at the surface of the printing cylinder such as nickel and the like.

Further in accordance with the invention, the peripheral recess 10a is located adjacent the opposite rounded corners of the printing cylinder and the ring 16 itself is of a material which at its exposed face may receive a coating of copper during the electroplating of the copper layer 13 on the face of the cylinder. In this manner, the copper layer extends over the cylindrical surface of the cylinder 10 down around the corners thereof and itself forms an electroplating seal with the locking ring 16 down to and into butting relation with the inturned cylindrical portion of the flange of the protecting sleeve.

Locking ring 16 may also be made of synthetic resins, similar to those already described, so as to further provide a more consistent noncorrosive assembly a well as a more leakproof seal.

While there has been described a typical and preferred embodiment of the invention, it is, of course, to be understood'that changes may be made within the spirit and scope of the appended claims.

What is claimed is:

1. The combination comprising a printing cylinder hava cylindrical printing surface and an end face,

a shaft extending from said end face of said cylinder for rotatably supporting said cylinder, and

a peripheral recess in said end face having two opposed Walls,

a protective sleeve of a material inert to electroplating baths, printing inks, and etching solutions, said sleeve having:

a cylindrical portion disposed in close fitting relationship on said shaft and extending from said end face along an exposed portion of said shaft,

a flange portion covering said end face, and

a cylindrical extension extending from the periphery of said flange portion, said cylindrical extension being disposed against one opposed Wall in said peripheral recess,

a locking ring disposed in tight-fitting relationship against said cylindrical extension and against the other opposed wall in said peripheral recess to secure said cylindrical extension within said recess to form a leakproof seal, and

a slinger ring having an overhanging lip clamping said cylindrical portion tightly to said shaft to form a leakproof seal.

2. The combination of claim 1 in which said cylindrical portion and flange portion consist of a synthetic resin selected from the group consisting of polytetrafluoroethylene and polychlorotrifluoroethylene.

3. The combination of claim 1 in which the cylindrical portion of said sleeve has a thickness greater than said flange portion.

4. The combination of claim 3 in which said flange portion has a conical section adhesively secured to and forming an extension of said cylindrical portion.

5. The combination of claim 1 in which said locking ring has an exposed surface, and in which said printing surface is electroplated with an extension of the electroplated surface covering said exposed surface to form an electroplated seal overlying said ring.

6. The combination of claim 1 in which said locking ring and said slinger ring consist of a synthetic resin selected from the group consisting of polytetrafluoroethylene and polychlorotrifiuoroethylene.

7. The combination recited in claim 1 wherein said slinger ring includes a rounded outer periphery, said slinger ring being disposed in shrink-fit relationship on said shaft, said cylindrical portion being disposed under said oglerhanging lip to clamp said cylindrical portion to said 5 aft.

References Cited by the Examiner UNITED STATES PATENTS 850,317 4/1907 Ridgely 29-119 1,801,396 4/1931 Thatcher 29123 X 1,83 1,645 11/193 1 Ballard 10140l 2,625,735 1/1953 Hitov. 2,650,603 9/ 1953 Howes 134-122. 2,918,069 12/1959 Brown et al 29 1 19 X 2,925,088 2/ 1960 Roscoe 29-132 X 2,948,773 8/1960 Hawes. 3,067,056 12/ 1962 Remer 101364 X FOREIGN PATENTS 189,147 4/ 1906 Germany. 531,155 12/1940 Great Britain.

References Cited by the Applicant UNITED STATES PATENTS 1,498,180 6/ 1924 Linder. 1,708,084 4/ 1929 Doane. 1,831,645 11/1931 Ballard. 2,029,011 1/ 1936 Bart. 2,127,824 8/ 193 8 Leuchter. 2,356,007 8/ 1944 Sanders. 2,435,872 2/ 1948 Coulson. 2,608,982 9/ 1952 Zademach et al. 2,650,603 9/ 195 3 Howes. 2,676,599 4/ 1954 McHenry. 2,726,492 12/ 1955 Vegell. 2,734,778 2/ 1956 Cook. 2,776,256 1/ 1957 Eulner et al. 2,817,562 12/1957 Fleming et al. 2,852,450 9/ 1958 Mundell. 2,989,966 6/ 1961 Marshall.

FOREIGN PATENTS 267,91 1 9/ 1927 Great Britain.

OTHER REFERENCES Rotogravure, A Survey of European and American Methods, by H. M. Cartwright, F.R.P.S. and Robert Mac- Kay, MacKay Publishing Company, Inc., Lyndon, Ky.

ROBERT E. PULFREY, Primary Examiner.

I- I H ant Exam ne 

1. THE COMBINATION COMPRISING A PRINTING CYLINDER HAVING: A CYLINDRICAL PRINTING SURFACE AND AN END FACE, A SHAFT EXTENDING FROM SAID END FACE OF SAID CYLINDER FOR ROTATABLY SUPPORTING SAID CYLINDER, AND A PERIPHERAL RECESS IN SAID END FACE HAVING TWO OPPOSED WALLS, A PROTECTIVE SLEEVE OF A MATERIAL INERT TO ELECTROPLATING BATHS, PRINTING INKS, AND ETCHING SOLUTIONS, SAID SLEEVE HAVING: A CYLINDRICAL PORTION DISPOSED IN CLOSE FITTING RELATIONSHIP ON SAID SHAFT AND EXTENDING FROM SAID END FACE ALONG AN EXPOSED PORTION OF SAID SHAFT, A FLANGE PORTION COVERING SAID END FACE, AND A CYLINDRICAL EXTENSION EXTENDING FROM THE PERIPHERY OF SAID FLANGE PORTION, SAID CYLINDRICAL EXTENSION BEING DISPOSED AGAINST ONE OPPOSED WALL IN SAID PERIPHERAL RECESS, A LOCKING RING DISPOSED IN TIGHT-FITTING RELATIONSHIP AGAINST SAID CYLINDRICAL EXTENSION AND AGAINST THE OTHER OPPOSED WALL IN SAID PERIPHERAL RECESS TO SECURE SAID CYLINDRICAL EXTENSION WITHIN SAID RECESS TO FORM A LEAKPROOF SEAL, AND A SLINGER RING HAVING AN OVERHANGING LIP CLAMPING SAID CYLINDRICAL PORTION TIGHTLY TO SAID SHAFT TO FORM A LEAKPROOF SEAL. 